1. Field of the Invention
The present invention relates to luminescent display devices, and particularly to an active-matrix luminescent display device which includes a luminescent element and a driving circuit having a capacitor and a thin-film transistor.
2. Description of the Related Art
Conventionally, there is an active development of luminescent display devices, such as organic electroluminescent elements (hereinafter abbreviated as organic EL elements), in which luminescent elements that control the luminance using an electric current are two-dimensionally arranged. In particular, there is an ongoing development of active-matrix luminescent display devices in which pixel circuits are arranged which include, for each luminescent element, a driving circuit for driving the luminescent element.
The driving circuit generally includes: a switching transistor which selects a pixel for producing luminescence; a driving transistor which drives a luminescent element; and a capacitor. The driving circuit includes, for example, a capacitor which holds a voltage for determining an amount of a current passed by the driving transistor (see Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2006-330736).
FIG. 1 shows the layout of a luminescent pixel 700 included in a conventional luminescent display device disclosed in Patent Literature 1. As shown in FIG. 1, the luminescent pixel 700 is wired with a signal line 705, a scanning line 706, and a power line 707. Further, the luminescent pixel 700 includes a switching transistor 701, a capacitor 702, a driving transistor 703, and a luminescent element 704. The luminescent element 704 is formed in the luminescent region of the luminescent pixel 700, whereas the switching transistor 701, the capacitor 702, and the driving transistor 703 are formed in the driving circuit region.